Nanoapertures in metal films at the ten nanometer scale can aid strong plasmonic enhancements that are potentially useful for biological and chemical sensing. Such nanoapertures have also been shown to be applicable to a highly promising method for DNA sequencing and biological and chemical sensing. However, to reliably and cost-effectively manufacture these nanoapertures on commercially-viable scales remains challenging. Current approaches to create such nanoapertures in metal films falls into three major categories—(a) metal evaporation on nanopatterned templates defined by electron beam or photolithography followed by metal liftoff, (b) focused ion beam milling, and (c) wet or dry etching using a nanopatterned mask. There are significant limitations associated with each of these methods as all of these methods have limited throughput, yield and resolution. This is a significant impediment for the commercialization of such devices.
Thus, what is needed is a method for fabrication of nanoapertures in metal film which at least partially overcomes the drawbacks of present approaches and provides improved resolution, yield and throughput. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the disclosure.